1. Field of the Invention
This invention relates broadly to electrical receptacles into which connector plugs are inserted to supply current to the power cord to which the plug is connected. More particularly, it concerns safety shutters for such receptacles which prevent a foreign object, e.g., a nail, when inserted into the receptacle form reaching the energized internal contacts of the receptacle.
2. Description of the Prior Art
Children and others frequently attempt to put foreign objects, such as nails, into electrical receptacles resulting on occasion in serious injury. Hence, a host of "safety" receptacles have been developed to prevent such improper entry which can be divided into several general classes. One class is the internal switch type which does not inhibit the insertion of foreign objects, but rather permit the existence of voltage in the receptacle only when is is properly used (see U.S. Pat. No. 4,271,337).
Another class is the "shuttered" type in which the insertion of anything other than the blades of an correct electrical plug is inhibited by some shutter means positioned behind the faceplate. Examples of such type receptacles are disclosed in the following patents.
U.S. Pat. Nos. 2,528,014, 4,168,104 3,238,492, 4,271,337 3,986,763, 4,379,607 4,072,382, 4,544,219.
The present invention provides an improved form of the shuttered type electrical receptacle.